thanks for the web site above i looked they have some good deals there and are very helpful to,i have been thinkin of putting a twelve valve in my 94 f 350,now with that web site and their parts i know i am gonna do the swap :c:

is your ford a f-350 or f-250?:tu:

Looks like a F-250, judging by the hubs...:w2:

ive heard the ac on the firewall is a problem with these conversions? any truth to that?

You mean the hvac blower system on the passenger side?

My turbo clears it just fine.

Nice work Matt, what was in it before?

Swapping in a 12 valve bring in an interference issue with the HVAC due to how the exhaust manifold throws the turbo out to the side. If you flip the manifold on a 12 valve, it brings the turbo up and closer to the engine which clears everything just fine. The common rail motors have a manifold that puts the turbo down and close to the rear of the block, which clears the HVAC just fine. There are "industrial" manifolds for the 12 valves that do the same...they were used in tractors and cabover trucks with the 5.9 Cummins...I have one on my donor motor for my Fummins and it clears everything great, also makes the downpipe shorter.

what about a 24 valve 98.5-02? does it have the same problem as the 12v or did they use a different manifold

Thanks. It had a 351 in it. It is a weird truck, it was ordered by a guy here in town and has everything heavy duty for an f 250 but with the small block and 3:55 gears. It has the dana 50ttb as opposed to the 44ttb that most small block trucks came with. Waiting for a solid axle 60 to pop up close and going to swap it over. Runs and drives great at the moment, just want to have the better axle.